Hand warmer



FIG. 1 is a front elevation view of the hand warmer of my new design;

FIG. 2 is a left side elevation view thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a bottom plan view thereof.

The broken lines in FIG. 3 and FIG. 4 form no part of the claimed design. 

CLAIM The ornamental design for a hand warmer, as shown and described. 